How important are horizontal dropouts?!

I was advised against building a fixie from an old steel frame that did not have horizontal dropouts. But I've seen (on this board and around town) plenty of fixies with all manner of dropouts...what gives? Why are horizontal dropouts desirable/necessary anyway? As you can tell, I'm new to SS/FX. Can someone drop some science on me?

There are not "all manners of dropouts" -- they're either semi-horizontal (the dropouts open towards the front and slope down), vertical (one small notch with a hangar that allows for a multi-speed wheel's axle), or completely horizontal (track ends).

You don't want to use vertical dropouts because they cause a headache when adjusting chain tension. But old steel frames on the whole didn't have verticals. So I'm assuming you mean you have semi-horizontal dropouts, which are just fine to build with.

Because the chain is not going to be perfectly tight without having to move the wheel slightly forward/backwards, and the horizontal drop out allows you to do that. Vertical dropouts are designed to keep teh wheel in one place while the derailleur applies tension to the chain. You can mimic this with a chain tensioner: http://www.performancebike.com/shop/...slisearch=true which can apply tension to the chain to keep it tight.

For SS, yes. If going fixed as the OP mentioned, then you can't rely on a tensioner. Fixed is still possible with vertical dropouts (e.g. eccentric bb, messing with chainrings, cogs, and half-links), but I wouldn't endure that headache without some very compelling reason.

As already mentioned in post #2, semi-horizontal drop-outs are fine. They're actually termed "horizontal" dropouts and common to most conversions. Track ends are truly horizontal but uncommon outside of track frames. You can find the details on Sheldon's site: http://www.sheldonbrown.com/fixed-conversion.html.

As already mentioned in post #2, semi-horizontal drop-outs are fine. They're actually termed "horizontal" dropouts and common to most conversions. Track ends are truly horizontal but uncommon outside of track frames. You can find the details on Sheldon's site: http://www.sheldonbrown.com/fixed-conversion.html.

?? By messing with the chain you mean removing it? This isn't necessary with horizontal dropouts either.

Sorry I'll be a bit more precise next time. when changing your gear ratio with track ends, adding or removing a chain link isn't usually necessary. if you have a road frameset with vertical or angled dropouts there isn't as much leeway.

hypothetically, your at the velodrome an you decide to go a gear higher, you could swap your chainring or cog, adjust the rear wheel and be back on the track before the practice session ends.

Vonzip, both track ends and horizontal dropouts are available in a variety of lengths. Some track ends are obnoxiously short and some dropouts (e.g. Simplex and the Campagnolo 1010) are quite long. It is true that the longest track ends are likely longer than the longest horizontal dropouts, but you're really overestimating how much this matters. On a conversion that I own that has sizable horizontal dropouts, I can put on a cog with two more teeth with no problem, assuming that my chain was properly sized initially. If anything, when it comes to swapping wheels, horizontal dropouts make for faster changes.

That all said, I like the look of track ends and find them to be perfectly functional, but your argument that they're superior for swapping gearing is specious at best.

I became a bike messenger in NYC in 1992 using my father's bike, which was a 10 speed road bike. I don't remember the name but I know it was really nice. Eventually I went through a lot of frames riding SS freewheel conversions. When I switched to fixed gear in 1995, still with the conversions, I always had problems with the rear wheel moving, the chain getting loose, etc. especially under the daily grind working in the city. I had a wheel pop completely out, and since the seat tube is typically farther away on a road frame the wheel can travel more.

It was unsafe. Finally I scored a Miyata frame with horizontal dropouts. I then knew what riding fixed gear was all about. Now I will not even go close to a conversion. I know a lot of people disagree, and there are some frames that are beautiful to be used for conversions. But when you depend on your chain to stay tight & your rear wheel to stay put, it becomes a gamble.

But I feel like if it wasn't made to be ridden with a fixed gear, then it shouldn't be converted. Period.

Vonzip, both track ends and horizontal dropouts are available in a variety of lengths. Some track ends are obnoxiously short and some dropouts (e.g. Simplex and the Campagnolo 1010) are quite long. It is true that the longest track ends are likely longer than the longest horizontal dropouts, but you're really overestimating how much this matters. On a conversion that I own that has sizable horizontal dropouts, I can put on a cog with two more teeth with no problem, assuming that my chain was properly sized initially. If anything, when it comes to swapping wheels, horizontal dropouts make for faster changes.

That all said, I like the look of track ends and find them to be perfectly functional, but your argument that they're superior for swapping gearing is specious at best.

point taken, but isn't asking 800 for a 580 frameset also a specious.. f a i l

an in the end, I'm always stoked to see a fixed rider no matter how much cash they dropped

Just get a real track frame. You don't want to risk that rear wheel walking out from under you when you lock up your legs.

I personally despise conversions.

There. I said it.

Pearls of wisdom from the poorly informed. If you have a rear wheel "walking out", then you haven't put it in correctly.

This is Africa, 1943. War spits out its violence overhead and the sandy graveyard swallows it up. Her name is King Nine, B-25, medium bomber, Twelfth Air Force. On a hot, still morning she took off from Tunisia to bomb the southern tip of Italy. An errant piece of flak tore a hole in a wing tank and, like a wounded bird, this is where she landed, not to return on this day, or any other day.